Dyslexia is a specific difficulty in learning to read that affects 5–12% of the population. Children with dyslexia struggle with reading despite having normal intelligence, no psychiatric and hearing disorders, and appropriate schooling. In dyslexia, the earlier the treatment starts, the better the compensation is. It is therefore extremely important to detect this reading disorder as early as possible, thereby limiting its disastrous consequences with appropriate remediation. Indeed, dyslexia often leads children to despise school, lowers their self-esteem, and impacts their social behaviour for the rest of their life. Today, we still lack early detection tools, and cost-effective remediation procedures. Our ultimate long-term goal is to provide novel identification and remediation tools for dyslexia.
In a significant proportion of individuals, deficits associated to dyslexia are thought to arise from difficulties in processing speech sounds. In particular, these difficulties are most evident when speech sounds are embedded in a background noise. But is there a trace of these difficulties in children’s brain activity that could be used for early identification? And if so, can we modulate the brain activity to improve speech processing and in turn reading skills? These are the two main questions that will be addressed in this project.
To answer the first question, a large group of children will be studied, some with normal reading skills and some with dyslexia. They will attend audio-visual stories in which sound will be mixed with noise. Their brain activity will be recorded by magnetoencephalography. Such recordings will make it possible to quantify how well their brain activity tracks the speech sounds of the person telling the story. The ultimate goal is to demonstrate that tracking is altered in children with dyslexia, in a way that predicts their reading skills. Hence, successful findings could lead to the development of a novel tool for early identification of dyslexia.
As a preliminary step to answer the second question, some participants will be trained to boost the way their brain activity tracks heard speech sounds. They will listen to continuous speech sounds and see in real time how well their brain tracks the speech sounds they are trying to hear. The technique to do that is called “neurofeedback”: brain activity will recorded with magnetoencephalography, processed in real time, and fed back to the participants. By seeing how well they track speech sounds, participants should be able to improve this tracking. If this is confirmed, some further studies will be designed to evaluate whether speech perception is improved by such neurofeedback procedure. And ultimately, whether such repeated neurofeedback training can improve reading skills.
